Cocaine addiction has been a major health and public safety problem throughout the past decade. Although much treatment research has been directed at the cocaine problem, progress has not been satisfactory. Studies have been hampered by high treatment dropout; those seeking treatment are characterized by a high degree of ambivalence about quitting cocaine use, and the immediate reinforcement of attending treatment is often unable to compete with the allure of cocaine. The Transtheoretical Model of Change (Prochaska & DiClemente, 1983) holds promise for intervening with cocaine users, because it attempts to explain why treatment efforts are often stymied by "motivational problems" or high drop out. The model posits five stages of change, Precontemplation, Contemplation Preparation, Action, and Maintenance, through which people move when changing a problem behavior. It also proposes ten basic processes and five levels of change. If interventions are not properly adjusted to client stage, processes, and level of change, drop-out is expected to be high and treatment success low. This revised proposal is for a three year project to adapt and refine assessment tools for crack, cocaine, and amphetamine users based on the Transtheoretical Model. The project will seek to modify existing measures of Transtheoretical Model constructs to make them appropriate for use with street drug users. This will involve focus interviews with 20 street stimulant users to collect qualitative data that will assist in modifying current measures and developing two new measures. Then, revised measures will be administered on three occasions to 300 stimulant users to evaluate the measures' reliability and validity. The project will also evaluate whether street stimulant users who are at the Contemplation stage of change can be identified and recruited to participate in a "Motivational Enhancement" intervention. A manual for this intervention will be adapted from approaches used with alcoholics and marijuana users, Street Outreach Workers will be trained to deliver the intervention, and a pilot test will be conducted to see whether these workers can consistently deliver the intervention. Street Outreach Services and Evergreen Treatment Services will recruit stimulant abusers for the assessment and intervention portions of the project. The project will produce data on the reliability and validity of measures of stage of change, processes of change, decisional balance and level of change to evaluate Transtheoretical Model constructs with this population. It will also provide information on the possibility of consistently conducting a stage-based intervention with a sub-set of this population.